


Test the hypothesis

by Chokemeplease



Category: Dangan Ronpa - All Media Types, New Dangan Ronpa V3: Everyone's New Semester of Killing
Genre: Blow Jobs, College AU, M/M, Ouma not Oma, Porn With Plot, almost a foot job, blowjob in the classroom, corny shumai jokes, happy birthday noots!, no beta we die like men, senpai/kouhai dynamics
Language: English
Status: Completed
Published: 2019-12-26
Updated: 2019-12-26
Packaged: 2021-02-25 23:47:46
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,001
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21973819
Author URL: https://archiveofourown.org/users/Chokemeplease/pseuds/Chokemeplease
Summary: The only way for Saihara to find out if the rumours about Kokichi Ouma were true was to test it out himself.Right?
Relationships: Oma Kokichi & Saihara Shuichi, Oma Kokichi/Saihara Shuichi
Comments: 17
Kudos: 170





	Test the hypothesis

**Author's Note:**

  * For [HereComesAComment](https://archiveofourown.org/users/HereComesAComment/gifts).



> Happy birthday to my bff nooty! Hope you enjoy <3

  
Kokichi Ouma was quite a well-known character in their college. His reputation preceded him. From being the son of a yakuza boss to a leader of a local gang, the rumours ranged from scary and frightening to… something else. Too often had Saihara heard whispers about how Ouma was the school slut, who would drop to his knees for a ten. He heard about how Ouma slept his way up to the dean’s list and cheated his grades. But the rumours were just that. Rumours. No one had conclusive evidence, and Saihara knew that rumours tended to get blown up.  
  
It was hard to ignore all the rumours. His detective mind spun towards the unsolvable, the mysterious, and he hadn’t been this distracted since he first heard about aliens as a child. He wanted answers. He wanted a definitive conclusion. Who _was_ Kokichi Ouma? The only class he shared with the boy was criminal forensic psychology. Whenever there was a particularly gruesome tidbit or picture, Ouma cooed and gasped like a delighted little boy watching a hero movie. When everyone grimaced and looked away, Ouma watched on with sparkling eyes.  
  
That didn’t tell him much, except that Kokichi Ouma was a weirdo.  
  
However, Saihara believed in cold, hard facts. Any reliable information about Ouma was good information over the rumours. Ouma’s fascination with the morbid could link to criminal history, but it was nothing decisive yet. Checking through the student files in the office, he learned about the boy’s age. Nineteen, a first-year student who had yet to decide his major. He was taking a variety of subjects, such as literature, sociology, psychology, law and English. He was Saihara’s junior, then.  
  
His emergency contact was his guardian, who didn’t share the same surname. Strange. What of Ouma’s parents? His student record was impeccable thus far. Ouma entered with a scholarship but was not part of any club activities. Most first-year students were in one, although it wasn’t mandatory. There were no disciplinary issues. His first semester had straight As in economics, global studies, history, engineering and computing. There was no clear area of specialization despite the university requiring them to pick their major in their second year.  
  
At the sound of footsteps, Saihara closed the file, sliding it back in place among the shelves. He made a show of lifting the stack of printouts on the teacher’s desk, setting it down as the door opened.  
  
“Oh, Saihara-kun. Thank you for collecting the printouts.”  
  
“It’s not a problem professor,” Saihara nodded, exiting the scene naturally. He managed to get enough information from the file before someone entered the staffroom.  
  
Ouma was always nowhere to be seen after classes. The boy seemed to run off after class, too quick for Saihara to follow. Saihara was unable to find him anywhere on campus other than when it was almost time for class. The younger student would bounce into class with a cup of hot drink. It smelt like hot chocolate. He’d spend time texting on his phone before the professor came, and he liked to swing his feet beneath his chair. They didn’t touch the ground, because Ouma was shorter than the average male.  
  
Ouma was slender, in a way that indicated a lack of regular bodybuilding or sports. It would be hard for him to be in the yakuza or a gang unless he wasn’t the type to get his own hands dirty. Gun usage or leadership was plausible. It couldn’t be ruled out yet. The way Ouma frequently answered in class and asked questions was curious and childlike, but clearly intelligent and engaged. His pencil case was a little teddy bear with a zipper on its belly, and he used fountain pens. The disparity was a little jarring, especially when he doodled on his notebooks.  
  
Was the contrast on purpose? It was difficult to place Ouma into any category. He seemed to get along well with everyone in class when they spoke to him, yet he didn’t seem to be in a clique or friend group. Some of the people he spoke with, it wasn’t clear if they were friends at all, based on how Ouma teased them and how upset they got.   
  
Today was different.  
  
Today, Ouma stayed behind in the classroom, sitting in his seat and waving goodbye to those who greeted him. Until there was no one left in the classroom except for both of them. Strange. What was Ouma staying back for?  
  
“You’ve been watching me, haven’t you? Saihara-senpai.”  
  
Saihara flinched from Ouma’s voice breaking the silence. The boy turned around in his seat. The smile on his face was curious and innocent. “Need something from me?”  
  
Well.  
  
Saihara never expected a situation like this. He thought he’d been rather covert in his observations. Ouma appeared to be sharper than he let on.  
  
“Watching you? Why would you think something like that?” Saihara offered, hoping it was sufficiently convincing.  
  
Ouma’s smile grew wider. It unnerved Saihara. With a laugh, the younger male stood up, walking over to where Saihara was sitting. He certainly had an interesting fashion sense, with his all-white ensemble, except for his black thigh highs. Still, when Ouma stood next to him, he was almost the same height as Saihara, who was sitting down. Ouma was so short, he seemed much younger than he was on file, like a little boy.  
  
“A little boy? How rude, I’m a full-grown adult you know,” Ouma pouted theatrically.  
  
Saihara blinked in surprise. “I didn’t say that.” He didn’t, did he? Sometimes he spoke out loud to himself while working on cases, but he was _aware_ of speaking aloud during those times.  
  
“You thought about it!” Ouma accused, a face full of mock offence.  
  
_Is he reading my mind?  
  
_ “Yes, I can read minds.”  
  
Ouma’s smile turned sly when Saihara stared at him incredulously. Saihara tried to think about all sorts of things to test that hypothesis. _Clap if you can hear me_ . Nothing. Ouma snickered at his confused look.  
  
“Look, you really believed that? I think you’re the little boy in this situation, senpai,” Ouma snickered, hopping up to sit on the desk so he could look down at Saihara instead of being at eye level. “So? Why have you been staring at me, you creep? Have you been stalking me?”   
  
Creep? Saihara flushed at the accusation.  
  
“I haven’t. I was just curious about you,” Saihara explained, watching Ouma’s purple eyes glimmer with interest. It was hard to talk face to face with someone so attractive and confident. “I wanted to ascertain for myself if the rumours were true instead of believing them blindly.”  
  
“Of course. I wouldn’t expect any less from THE Shuichi Saihara, a detective who’s been solving cases since his highschool days,” he grinned at Saihara’s surprise. “Well, did you think you were the only one who could look up student files? Two can play the game. And? What have you found out?”  
  
Ouma’s expression shifted rapidly to one that was haughty and guarded. Saihara felt like he had to step lightly. It was strange, how much attention Ouma commanded despite being smaller in size. His presence felt overwhelming and intimidating.  
  
“Not much. You’re ambidextrous. You favour your black pen over your blue. You use your purple pen for underlining.”  
  
“Creeeeeepy,” Ouma dragged out the world, leaning away from Saihara. He faked an expression of being frightened and disgusted. “Do I need to call the cops? File a restraining order? Are you obsessed with me? Ew.”  
  
Even though Saihara knew it was clearly an act, he still felt as if something didn’t sit quite right. It’s true that in his pursuit of truth, he had been too attentive to Ouma. “Sorry. I’ll drop the investigation if it makes you uncomfortable.”  
  
“No, that’s boring,” Ouma pouted, leaning back in. “Ask me questions, I’ll answer them. Well? You won’t get a better opportunity than this, would you?”  
  
That much was true. Saihara nodded in resolve, taking out his notebook.  
  
“Are you the son of a yakuza head?”  
  
“Of course!”  
  
“Are you the leader of a local gang?”  
  
“Mmhm!”  
  
“Are you sleeping with your professors for your grades?”  
  
“Every single one.”  
  
The way Ouma readily agreed to everything with a bright smile meant he clearly wasn’t taking this seriously. Saihara did not gain any new answers. Ouma’s body language was impeccable. Saihara was unable to tell what was truth or what was a lie. He couldn’t help but feel that Ouma would make a fantastic criminal.  
  
“You ought to test the hypothesis yourself, wouldn’t you say?” Ouma cooed. He batted his eyelashes suggestively at Saihara. With his left foot, he pressed the tip of his boot against Saihara’s chest, drawing a line lower and lower. Saihara swallowed at the implications. “Well, detective?”  
  
“Stop playing around,” Saihara retorted weakly. He stopped breathing when Ouma’s shoe stopped on his crotch. Ouma stepped down, and the pressure caused Saihara to gasp, mouth falling open. “Ouma…”  
  
“Class is in session, Saihara-senpai. Right not, we’re having an experiment. An experiment to test if the rumours hold any weight,” Ouma said coquettishly. Tapping a finger against his lip, he couldn’t resist a smile when he dug his heel in, causing a guttural moan to slip out of Saihara’s mouth. The detective slapped a hand over his mouth, thoroughly embarrassed. “No need to be shy. There are no longer any classes in this room, so no one will come in any time soon. Feel free to be loud and participate _enthusiastically_. I’ll give you bonus marks, okay?”  
  
Ouma seemed to be breathing harder as well, visibly affected by the situation. He rubbed Saihara’s crotch in circular motions. “Hey, senpai… Don’t you want more? Or do you want to cum from my foot? Surely that would please a pervert like you.”   
  
Saihara moaned weakly in response. He didn’t have the willpower to stop Ouma. He didn’t want to end this situation. He’d never experienced a sexual pleasure like this before. This was so much different compared to touching himself. With Ouma touching him, giving him all of his attention… it caused his entire body to flare up with sensitivity, aching to be touched. The fear of someone walking into this caused him to protest.  
  
“Ouma, stop…”  
  
“Do you really want me to?” Ouma laughed knowingly. His laugh was breathy and airy, and it did things to Saihara. It was like Ouma saw right through him instead of the opposite. It felt like their roles had reversed, and it was Saihara under scrutiny right now.  
  
Ouma grinned sharply, brushing his fingers across his lips. Opening his mouth, he slipped a finger in. He made a show of rubbing it across his tongue. When he was sure he had Saihara’s undivided attention, he closed his ruby red lips around his digit, slowly sinking lower as he sucked on it. They never broke eye contact throughout his performance, as the finger disappeared completely into Ouma’s mouth. Swallowing painfully, Saihara felt his dick twitch in interest. He wanted that hot and mischievous mouth wrapped around his cock.  
  
Ouma released the finger with a loud pop. Saihara found himself unable to look away from Ouma’s moist lips as they curved into a smile. “Hey… I’m better with my mouth than my foot. Do you believe me?”  
  
Saihara had caught on to the game and scenario by now. “I need to test it.”  
  
“That’s good. Because I’m hungry, Saihara-senpai. I want your shumai in my mouth,” he giggled at his own joke. Hopping off the desk, he sank to his knees so fluidly he was on the ground before Saihara even blinked. With his slender fingers, he parted Saihara’s thighs, settling between them. “This is experiment number 1. We’ll need repeated trials to make sure it’s a consistent result, won’t we?”  
  
His hands were warm even through the fabric of Saihara’s pants. The detective was highly aware of the sensation of those hands, how they rubbed little suggestive circles. Saihara was dazed, and it took him a while to realize Ouma was waiting for a reply. “Yeah, we do.”  
  
Ouma gave a pleased smile as he undid Saihara’s belt, tossing it aside without a care. The way he concentrated on the task at hand turned Saihara on. His erection was pushing against the fabric of his pants.  
  
“Someone’s eager. I didn’t know Mister honour student would get the hots for being sucked off in the classroom,” Ouma teased. He leaned in, mouthing against Saihara’s bulge. He breathed in deeply, basking in the nasty scent of Saihara’s precum. “Hey, wouldn’t it be a shame if I stopped right now?”  
  
At Saihara’s startled flinch, Ouma smiled, resting his head against Saihara’s thigh. He looked extremely pleased with himself and the power he held over Saihara. There was that cruel spark in his eyes that wanted to be a tease, wanted to see Saihara lose it, to beg him for what he wanted. Something about Saihara’s desperate expression must have stroked his fancy because Ouma laughed, lifting his head and resuming his actions.  
  
Ouma pulled down Saihara’s pants, freeing his aching cock. The sudden cool air caused him to gasp. Ouma took his time, marvelling at the sight of Saihara’s hard-on that was due to him. With a soft touch, he brushed his fingers against the throbbing vein along Saihara’s dick.  
  
“What a pretty colour,” Ouma cooed. He leaned in and pressed a kiss against the tip, a move that had Saihara holding his breath. He kissed along Saihara’s length reverently and slowly, as though savouring a treat. He mouthed Saihara’s balls, then licked a wet line back up to the tip. Before Saihara could protest how it wasn’t enough, Ouma opened his lips, taking Saihara into his mouth, as far as he could go.  
  
Ouma moaned when the girth of Saihara’s dick stretched his lips. It laid hot and heavy on his tongue. He worked up to a rhythm, bobbing his head as he sucked on Saihara’s dick. When he looked up through his lashes, Saihara was red-faced, hands pressed against his mouth to stop himself from moaning. His eyes were shut tight, and Ouma was having nothing of that. He pulled himself off, waiting for Saihara to look at him. At the loss of the pleasurable suction around his cock, Saihara opened his eyes, wondering what happened.  
  
“Senpai, it’s not fair if I’m making all these dirty, obscene sounds and you’re so quiet. Don’t look away from me. And keep your hands on my head, hmm?” Ouma said, in a tone that left no room for arguments. His pretty pout sealed it for Saihara. The detective nodded, carefully placing his hands on Ouma’s head, fingers carding through soft strands of purple hair. “You can tug if you want, I like some pain.”  
  
Ouma grinned up at Saihara. When Saihara tugged experimentally, Ouma gasped, his mischievous expression rapidly changing to one of pleasure. With renewed motivation, Ouma sunk back down on Saihara’s cock, switching an angle to suck Saihara in deeper. His cock bulged out against Ouma’s cheek. The wet sounds of sucking were lewd and loud, echoing around their classroom. The harder Ouma sucked, the harder Saihara pulled on Ouma’s hair as he was close to his climax. Without anything to hold him back, Saihara moaned loudly. He couldn’t stop himself from thrusting his hips to match Ouma, trying to get Ouma to quicken the pace.   
  
Ouma protested when Saihara slammed into his throat, again and again, fucking his mouth like a pussy. He had long since lost control. Even when he choked and gagged, Saihara didn’t let go, using him like a cocksleeve, enjoying the way Ouma’s throat convulsed around him. Drool dripped down messily. The pace was too quick, and even when Ouma whined and tried to back away, Saihara’s hands were tight around his head, preventing him from going anywhere. He was completely helpless. He moaned loudly and futilely as Saihara chased his orgasm.  
  
“Ah, fuck, I’m so close. Ouma, fuck…. I’m coming!”  
  
With a final thrust, Saihara held Ouma’s head down as he came. The hot splatter of cum hit Ouma in the back of his throat, and he had no choice but to swallow as he choked and gagged on Saihara’s dick. Saihara groaned, releasing Ouma when it was all over. He felt so relaxed after emptying his load. He breathed deeply, trying to catch his breath. Ouma coughed, backing up and wiping the back of his hand against his lips.  
  
“That was mean,” Ouma said hoarsely, pouting with teary eyes. His hair was a mess. “And it was my first time too.”  
  
“W-what? Really? I’m so sorry Ouma, it felt so good that I stopped thinking, and…” Saihara sat up straight, flustered and worried that he had hurt Ouma.  
  
“I was just kidding.” Ouma stood up shakily, but his grin was sure and strong. He pushed his hand through his hair, smoothing it back in place. “It’s cute how gullible you are, senpai. So? Did you get any answers yet?”  
  
Saihara shook his head slowly and dumbly. He’d learned nothing except that Ouma was good at giving head. However, he had no basis for comparison since it was the first blowjob he had ever received.  
  
“Sounds like you need more experimental trials,” Ouma snickered. “This one is free of charge, but you’re paying for the next one. A discount will be given for my beloved senpai, of course. Well then, get home safe. Thanks for the shumai.”  
  
“Shumai?” Saihara asked dumbly as Ouma walked back to his desk, grabbing his bag.  
  
“Your meat dumpling,” Ouma said cheekily as he slung the bag over his shoulder. “Maybe next time I can eat it in a different way, hmm? You could bend me over a desk just like in your wet dreams.”  
  
Saihara flushed as Ouma left the classroom, giggles trailing behind him. How did Ouma know he had a wet dream about that?  
  
Could dreams become a reality?  
  


**Author's Note:**

> Aaaa this is my first saiou fic so I hope I got their characterization right!


End file.
